Exercise before/after diving?

[InTheDrink]

I know what circular logic is. My question was just whether there's a difference between exercise underwater and exercise over water, if *exercise* is considered a potential risk in DCI.

I appreciate that there may be many other more important factors and I personally hydrate the hell out of myself but was just curious whether exercise with nitrogen in solution was comparable with nitrogen out of solution. I'm just trying to understand what risks there are and aren't.

 

[String]

Biggest "exercise" risk after diving is normally people climing back onto a boat, unloading and lifting their kit and stages back on then quite often recovering shotlines, recovering boat onto trailer and so on.
Often that CAN be quite strenuous but theres no avoiding it.

 

[seaducer]

I know what circular logic is. My question was just whether there's a difference between exercise underwater and exercise over water, if *exercise* is considered a potential risk in DCI.

I appreciate that there may be many other more important factors and I personally hydrate the hell out of myself but was just curious whether exercise with nitrogen in solution was comparable with nitrogen out of solution. I'm just trying to understand what risks there are and aren't.

I would avoid any exercise that drives your HR up. I would avoid running, cycling, and any high impact stuff. I would even avoid strength training.

As for diving after diving, if the dives are really strenuous then you should add extra time to your SI, and plan these dives with an extra level of conservatism. If they are just regular dives then you should follow whatever repetitive program you were taught for dive planning.

 

[ligersandtions]

I actually just read about exercising before/after diving in my "Deco for Divers" book recently. Here is what is said:

"Aerobic exercise in advance of diving is generally considered to reduce the risk if performed between 10 and 48 hours before the dive. Exercise more than 48 hours in advance of the dive seems to have no benefit and exercise less than 10 hours before the dive seems to counteract any benefits by potentially creating more gas nuclei. Intense or strenuous exercise before a dive should also be avoided."

If you want to exercise before diving, it's best to do it more than 10 hours in advance. You do not want to lift weights (or do strenuous exercise) on the day of diving as it can potentially create more nuclei.

 

[pt40fathoms]

I know what circular logic is. My question was just whether there's a difference between exercise underwater and exercise over water, if *exercise* is considered a potential risk in DCI.

I hope I didn't sound pithy in my use of the phrase, my intention was not to offend. You do pose an interesting conundrum here though, and the only way I can think of illustrating the difference is as follows.

During your dives you are in a near weightless environment, floating neutral in the water. You may be moving your legs with force and regularity, but that force is considerably less than what would be experienced if you were to exert yourself in the same manner out of the water on dry land. Or as String rightly points out, as you are climbing back on board the boat. At some point, if your nitrogen loading is sufficiently high enough, or you are in a dehydrated state, or your ascent was too rapid, or at times for no definable reason what so ever, you *may* experience a DCS event, while doing multiple dives and exerting yourself to a moderate or high degree. But you have stated that the one most important precautionary measure you can take, is one that you routinely follow, and that is to keep well hydrated.

Can anyone guarantee that if you follow a set of rules you will never experience a DCS event? Absolutely not. Their are documented cases with DAN that list a DCS event as an "undeserved DCS event". Simply meaning that they got bent for no reason that can be explained. They are rare, and you would have better odds of winning a lottery than experiencing an undeserved hit. The medical science on this is still growing, and may take decades before we fully understand all the inner workings that take place during a dive and subsequent surface interval. If we ever understand all if it at all. What we do know has made diving one of the safest recreational activities available, as long as we all follow the rules. (don't hold your breath, ascend slowly, keep hydrated, etc...)

I hope this answers your questions, and more importantly puts you at ease. It is highly likely that because you already take reasonably prudent steps to lessen your chances of a DCS hit, and appear to be quite level headed in this matter, that you will enjoy a lifetime of fun and exploration.

 

[pt40fathoms]

I actually just read about exercising before/after diving in my "Deco for Divers" book recently. Here is what is said:

"Aerobic exercise in advance of diving is generally considered to reduce the risk if performed between 10 and 48 hours before the dive. Exercise more than 48 hours in advance of the dive seems to have no benefit and exercise less than 10 hours before the dive seems to counteract any benefits by potentially creating more gas nuclei. Intense or strenuous exercise before a dive should also be avoided."

If you want to exercise before diving, it's best to do it more than 10 hours in advance. You do not want to lift weights (or do strenuous exercise) on the day of diving as it can potentially create more nuclei.

Interestingly enough, the source for some of the advancements in deco diving come from NASA. When an astronaut prepares to do an EVA and suits up, they reduce the pressure in their suit from 15 psi to a working pressure of 5 psi. This allows them to be able to bend their arms easier and experience less resistance in moving around in the suits. One of the problems with this is the very real danger of a DCS hit while reducing pressure. So the astronauts will ride a bicycle and pre-breath O2 before suiting up, in order to reduce the risk.

 

[vlkr]

gay d - were you a nav underwater swimmer?

 

[Gary D.]

gay d - were you a nav underwater swimmer?

From 64-70 I was.

Gary D.

 

[meierdierck]

I studied this years ago in college, recovery improves with fitness
its not just getting your heart rate into the 120-140 range, but how long it takes to recover after,
it would also have to do with your conditioning, & fitness levels
if you run 30-45 min every day, a 30 min run with an hour of recovery and fluids should be fine,
if you surf the couch and randomly decide to run 30 min and recover an hour before diving, it will create more stress on your body & system (esp if it is like mine)
pointis they better shape you are, easier/ quicker recovery like our navy boys

 

[vlkr]

gary d - eod, salvage, udt?